IBM PC compatible multi-chip module

ABSTRACT

A multi-chip module and a chip set that comprises a plurality of the multi-chip modules. The multi-chip module includes a plurality of functional circuits provided on a substrate, the circuits defining a plurality of signal inputs and outputs. A plurality of pins are secured in a single row along the periphery of the substrate and are connected to the inputs and outputs. The pins include a set of 91 signal pins, two ground pins, and a power pin, the signal pins having a configuration complying in number and signal type with the IEEE-P996 Requirements to define an ISA bus. The multi-chip module includes a rectangular housing wherein the pins, in the form of gull wing pins, extend laterally from a peripherally extending wall. The ISA bus pins extend along one side and partially along adjacent sides of the rectangular module. The functional circuits of one embodiment of the module include a CPU, serial interfaces, a parallel interface, a hard drive interface, a floppy disk interface, a keyboard interface, and flash memory. Other multi-chip modules can include a PCMCIA interface, an Ethernet interface, or a display controller.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent application Ser. No. 08/564,688 filed on Nov. 29, 1995 now U.S. Pat. No. 5,742,844.

FIELD OF THE INVENTION

This invention relates to a multi-chip module.

BACKGROUND OF THE INVENTION

The most successful applications of computer technology have been those that people do not see. Microcontrollers and microprocessors govern automotive anti lock braking systems, automatic teller machines, elevators, subway ticket systems, and medical equipment. These hidden computers, otherwise known as embedded systems, permeate our lives. The embedded control market is, in fact, growing significantly faster than the desk top computing market. A major trend is the move from 4- and 8-bit processors to more powerful devices that provide more computing power and enable more "friendly" man-machine interfaces. A study by Desk Top Strategies showed that in 1994 over 320 million 16- and 32-bit embedded control processors were shipped to original equipment manufacturers (OEMs) for use in embedded control applications. In contrast, only 50 million were shipped to desk top computer manufacturers. The compound annual growth rate for 32-bit processors in the embedded market from 1992 to 1997 is projected to be 53 percent, compared with an estimated 32 percent in the desk top market.

The area of greatest growth in the embedded control market is the segment of ultra-miniature controllers for portable and transportable instruments. OEMs have indicated a strong interest in developing products with the PC architecture, but have found that size, integration, power, reliability, or cost constraints make existing broad-level products unsuitable for their applications.

The Cardio 386 developed by S-Mos Systems comprises a full function, small footprint, X86 computer that includes a CPU, all standard PC-type I/O controllers, PGA graphics, floppy and hard disk drive interfaces, DRAM, flash memory, and transparent power management. It adopts a PC AT architecture which complies with the ISA (industry standard architecture) bus pin configuration. However, it makes use of a unique edge connector comprising a plurality of tracks formed into rows on a card. This is received in a complementary slot for connection to peripheral devices. The use of a connector for connecting the module to a board makes its implementation inherently unreliable since vibrations can compromise the electrical connections between the various tracks forming the pins, and the corresponding contacts of the slot connector. Furthermore, no provision is made for integrating the module with proprietary hardware of OEMs (original equipment manufacturers).

Another prior art device is the Northstar III by Micro Module Systems that comprises a multi-chip module, including a Pentium processor, a cache controller, and RAM incorporated in a 349 pin PGA package. Once again, no facility is provided for interfacing with OEM proprietary hardware, Furthermore, the North Star module is packaged in a 349 pin PGA which makes simple direct connection to peripheral devices impossible without complicated track layout design. Therefore it does not allow the module to be simply dropped into an OEM system.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to incorporate a multi-chip module in an ultra-miniature form factor. In particular it is an object of the invention to provide a module the size of a large integrated circuit.

It is a further object of the invention to provide an Intel X86 compatible computer module and peripheral controller modules wherein the computer module includes a CPU, I/O (a parallel port and two serial ports), a keyboard interface, a DRAM interface, floppy disk controller, hard disk controller, and flash disk functions based on Intel X86 architecture. Specifically, it is an object of the invention to provide a multi-chip module that provides an OEM (Original Equipment Manufacturer) with the facility for incorporating a feature set that is compatible with IBM PC/AT hardware, software, and bus pin configuration.

It is a further object of the invention to provide a module having low power consumption, broad thermal adaptability, low cost, and high reliability by eliminating cables and mounting hardware.

It is yet a further object of the invention to provide a module family having identical ISA bus pin configurations to facilitate easy interconnection.

It is yet a further object of the invention to provide a development board to form a platform for receiving a multi-chip module of the invention, thereby to provide for the quick development of pilot projects.

According to the invention there is provided a multi-chip module comprising a plurality of functional circuits provided on a substrate, the circuits defining a plurality of signal inputs and outputs, and a plurality of module pins secured in a single row along the periphery of the substrate and connected to the inputs and outputs, the module pins including a set of 91 pins, two ground pins, and a power pin, defining an ISA bus means, the signal pins having a configuration complying in number and signal type with the signal pins laid down under the IEEE-P996 specification, and as applied in the ISA (Industry Standard Architecture) requirements. For this reason it will hereinafter be referred as to as the ISA bus.

The module can be rectangular in shape, having a first side, a second side opposite the first side, a third side, and a fourth side, and is defined by an upper surface, a lower surface, and a peripheral wall, and wherein the plurality of pins extend from the peripheral wall.

The pins of the ISA bus means of the present invention preferably comprise: pin 38 corresponding to signal IOCHCK; pin 39 corresponding to signal SD07; pin 40 corresponding to signal RESETDRV; pin 41 corresponding signal SD06; pin 42 corresponding to signal SD05; pin 43 corresponding to signal IRQ9; pin 44 corresponding to signal SD04; pin 45 corresponding to signal SD03; pin 46 corresponding to signal DRQ2; pin 47 corresponding to signal DRQ2OUT-; pin 48 corresponding to signal SD02; pin 49 corresponding to signal SD01-; pin 50 corresponding to signal 0WS; pin 51 corresponding to signal SD00; pin 52 corresponding to signal IOCHRDY; pin 53 corresponding to signal SBHE-; pin 54 corresponding to signal MEMSC16-; pin 55 corresponding to signal AEN; pin 56 corresponding to signal SMEMW-; pin 57 corresponding to signal LA23; pin 58 corresponding to signal IOCS16-; pin 59 corresponding to signal SA19; pin 60 corresponding to signal SMEMR-; pin 61 corresponding to signal LA22; pin 62 corresponding to signal IRQ10; pin 63 corresponding to signal SA18; pin 64 corresponding to signal IOW-; pin 65 corresponding to signal LA21; pin 66 corresponding to signal IRQ11; pin 67 corresponding to GND; pin 68 corresponding to signal SA17; pin 69 corresponding to signal IOR-; pin 70 corresponding to signal LA20; pin 71 corresponding to signal IRQ12; pin 72 corresponding to signal SA16; pin 73 corresponding to signal DACK3-; pin 74 corresponding to signal LA19; pin 75 corresponding to signal IRQ15; pin 76 corresponding to signal SA15; pin 77 corresponding to signal DRQ3; pin 78 corresponding to signal LA18; pin 79 corresponding to signal IRQ14; pin 80 corresponding to signal SA14; pin 81 corresponding to signal DACK1-; pin 82 corresponding to signal LA17; pin 83 corresponding to signal DACK0-; pin 84 corresponding to signal SA13; pin 85 corresponding to VCC; pin 86 corresponding to signal DRQ1-; pin 87 corresponding to signal MEMR-; pin 88 corresponding to signal DRQ0; pin 89 corresponding to signal SA12; pin 90 corresponding to signal REFRESH-; pin 91 corresponding to signal MEMW-; pin 92 corresponding to signal DACK5-; pin 93 corresponding to signal SA11; pin 94 corresponding to signal SYSCLK; pin 95 corresponding to signal SD08; pin 96 corresponding to signal DRQ5; pin 97 corresponding to signal SA10; pin 98 corresponding to signal IRQ7; pin 99 corresponding to signal IRQ7OUT; pin 100 corresponding to signal SD09; pin 101 corresponding to signal DACK6-; pin 102 corresponding to GND; pin 103 corresponding to signal SA09; pin 104 corresponding to signal IRQ6; pin 105 corresponding to signal IRQ6OUT; pin 106 corresponding to signal SD10; pin 107 corresponding to signal DRQ6; pin 108 corresponding to signal SA08; pin 109 corresponding to signal IRQ5; pin 110 corresponding to signal SD11; pin 111 corresponding to signal DACK7-; pin 112 corresponding to signal SA07; pin 113 corresponding to signal IRQ4; pin 114 corresponding to signal SD12; pin 115 corresponding to signal DRQ7; pin 116 corresponding to signal SA06; pin 117 corresponding to signal IRQ3; pin 118 corresponding to signal SD13; pin 119 corresponding to signal SA05; pin 120 corresponding to signal DACK2-; pin 121 corresponding to signal SD14; pin 122 corresponding to signal MASTER-; pin 123 corresponding to signal SA04; pin 124 corresponding to signal TC; pin 125 corresponding to signal SD15; pin 126 corresponding to signal SA03; pin 127 corresponding to signal BALE; pin 128 corresponding to signal SA02; pin 129 corresponding to signal SA01; pin 130 corresponding to signal OSC; and pin 131 corresponding to signal SA00.

The pin of the ISA bus means of the present invention can alternatively comprise: pin 38 corresponding to signal SA00; pin 39 corresponding to signal OSC; pin 40 corresponding to signal SA01; pin 41 corresponding signal SA02; pin 42 corresponding to signal BALE; pin 43 corresponding to signal SA03; pin 44 corresponding to signal SD15; pin 45 corresponding to signal TC; pin 46 corresponding to signal SA04; pin 47 corresponding to signal MASTER-; pin 48 corresponding to signal SD14; pin 49 corresponding to signal DACK2-; pin 50 corresponding to signal SA05; pin 51 corresponding to signal SD13; pin 52 corresponding to signal IRQ3; pin 53 corresponding to signal SA06; pin 54 corresponding to signal DRQ7; pin 55 corresponding to signal SD12; pin 56 corresponding to signal IRQ4; pin 57 corresponding to signal SA07; pin 58 corresponding to signal DACK7-; pin 59 corresponding to signal SD11; pin 60 corresponding to signal IRQ5; pin 61 corresponding to signal SA08; pin 62 corresponding to signal DRQ6; pin 63 corresponding to signal SD10; pin 64 corresponding to signal IRQ6OUT; pin 65 corresponding to signal IRQ6; pin 66 corresponding to signal SA09; pin 67 corresponding to GND; pin 68 corresponding to signal DACK6-; pin 69 corresponding to signal SD09; pin 70 corresponding to signal IRQ7OUT; pin 71 corresponding to signal IRQ7; pin 72 corresponding to signal SA10; pin 73 corresponding to signal DRQ5; pin 74 corresponding to signal SD08; pin 75 corresponding to signal SYSCLK; pin 76 corresponding to signal SA11; pin 77 corresponding to signal DACK5-; pin 78 corresponding to signal MEMW-; pin 79 corresponding to signal REFRESH-; pin 80 corresponding to signal SA12; pin 81 corresponding to signal DRQ0; pin 82 corresponding to signal MEMR-; pin 83 corresponding to signal DRQ1; pin 84 corresponding to signal SA13; pin 85 corresponding to VCC; pin 86 corresponding to signal DACK0-; pin 87 corresponding to signal LA17; pin 88 corresponding to signal DACK1-; pin 89 corresponding to signal SA14; pin 90 corresponding to signal IRQ14; pin 91 corresponding to signal LA18; pin 92 corresponding to signal DRQ3; pin 93 corresponding to signal SA15; pin 94 corresponding to signal IRQ15; pin 95 corresponding to signal LA19; pin 96 corresponding to signal DACK3-; pin 97 corresponding to signal SA16; pin 98 corresponding to signal IRQ12; pin 99 corresponding to signal LA20; pin 100 corresponding to signal IOR-; pin 101 corresponding to signal,SA17; pin 102 corresponding to GND; pin 103 corresponding to signal IRQ11; pin 104 corresponding to signal LA21; pin 105 corresponding to signal IOW-; pin 106 corresponding to signal SA18; pin 107 corresponding to signal IRQ10; pin 108 corresponding to signal LA22; pin 109 corresponding to signal SMEMR-; pin 110 corresponding to signal SA19; pin 111 corresponding to signal IOCS16-; pin 112 corresponding to signal LA23; pin 113 corresponding to signal SMEMW-; pin 114 corresponding to signal AEN; pin 115 corresponding to signal MEMCS16-; pin 116 corresponding to signal SBHE-; pin 117 corresponding to signal IOCHRDY; pin 118 corresponding to signal SD00; pin 119 corresponding to signal 0WS-; pin 120 corresponding to signal SD01; pin 121 corresponding to signal SD02; pin 122 corresponding to signal DRQ2OUT; pin 123 corresponding to signal DRQ2; pin 124 corresponding to signal SD03; pin 125 corresponding to signal SD04; pin 126 corresponding to signal IRQ9; pin 127 corresponding to signal SD05; pin 128 corresponding to signal SD06; pin 129 corresponding to signal RESETDRV; pin 130 corresponding to signal SD07; and pin 131 corresponding to signal IOCHCK-.The ISA bus pins preferably extend along the first side and at least partially along the third and fourth sides. The multi-chip module can include 240 module pins.

The functional circuits in a module can include a central processing unit. The functional circuits can further include two serial interfaces, a parallel interface, a hard drive interface, a floppy disk interface, a keyboard interface, and flash memory.

Other modules can include functional circuits that include a PCMCIA interface, an Ethernet interface, or a display controller.

The substrate can comprise a printed circuit board and the functional circuits comprise semiconductor devices which can be packaged or can be in bare die form secured to the printed circuit board.

Further, according to the invention, there is provided a multi-chip module comprising a plurality of functional circuits encapsulated in a rectangular housing, the housing having an upper surface and a lower surface, and a peripheral wall extending along a first side, a second side opposite the first side, a third side, and a fourth side; and a plurality of pins extending laterally from the peripheral wall, wherein the pins include a set of 91 signal pins, two ground pins and a power pin defining an ISA bus means, the signal pins of which comply in number and signal type, with the signal pins laid down under the IEEE-P996, and as applied in the ISA (Industry Standard Architecture) requirements.

Still further, according to the invention, there is provided a module family comprising a plurality of functionally different modules, wherein each module has a plurality of pins and the pins of each module include a set of 91 signal pins, two ground pins, and a power pin, defining an ISA bus means, the signal pins of which comply in number and signal type with the signal pins laid down under the IEEE-P996, and as applied in the ISA (Industry Standard Architecture) requirements.

Each module can comprise at least one functional circuit encapsulated in a rectangular housing, the housing having an upper surface and a lower surface, and a peripheral wall extending along a first side, a second side opposite the first side, a third side, and a fourth side, and wherein the pins of the module extend laterally from the peripheral wall.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a multi-chip module of the invention;

FIG. 2 is a side view of the module of FIG. 1;

FIG. 3 is a block diagram of a multi-chip module of the invention;

FIGS. 4A and 4B are a schematic representation of the first embodiment of a multi-chip module of the invention indicating the configuration of the pins;

FIGS. 5A and 5B are a schematic representation of the alternative embodiment of a multi-chip module of the invention indicating the configuration of the pins;

FIG. 6 shows a PC board layout for a development board showing the mounting, site for the module of FIG. 1, and

FIG. 7 is a schematic representation of a number of different modules in accordance with the invention connected to each other by means of their ISA buses to form a module family of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

A need exists in the field of embedded applications for small, highly reliable computer systems that draw little power, are easy to integrate, have broad thermal adaptability and are relatively inexpensive. Applications for such devices include medical instruments, data logging devices, security systems, test equipment, point-of-sale terminals, communications devices, such as Internet and facsimile machines, and navigational instruments. OEMs (original equipment manufacturers) typically use the Intel X86 architecture since it offers the world's largest body of hardware and software. The present invention has accordingly been developed to address the problems in the prior art by providing a multi-chip module packaged to resemble a large integrated circuit chip comprising a 240 pin QFP having an overall footprint of 59.54×79.88 mm. The module includes a set of pins constituting a bus for connection to the OEM designer's proprietary internal hardware. The invention specifically contemplates providing this bus with a configuration complying with the ISA (Industry Standard Architecture) requirements. This will allow the OEM designer quickly to incorporate IBM PC/AT hardware and software and to implement the module in ISA compatible proprietary product designs. The module is now described in greater detail with reference to FIGS. 1 and 2 which show a plan view and a side view, respectively, of the module.

The module 10 is a 240 pin QFP with gull wing pins having a 0.762 mm. pitch. The body is rectangular, the one side of which measures 76.2 mm and the overall footprint in this embodiment being 59.54×79.88 mm. The pins themselves are typically 0.5 mm wide, and the dimensions of distances 12 and 14 in FIG. 1 are 3.5 mm for this embodiment. By using a chip-like package in which the pins are formed around the periphery of the module 10 in a single row as illustrated in FIGS. 1 and 2, the module 10 can easily be soldered into place to form a very sturdy, reliable set of connections. Furthermore, tracks can be designed to lead directly from the pins to another device by making use of PC board tracks on one or both surfaces of the PC board without the need for several layers to route the various tracks. Since the pins are soldered directly to the interconnecting tracks, the system has inherent reliability in that it eliminates cables and mounting hardware that could otherwise vibrate loose. As many as half a dozen interconnecting cables, assorted connectors and mounting hardware required with many existing prior art single board computers, are thereby eliminated.

The module thus provides an Intel X86 compatible computer in an ultra-miniature form factor that can be integrated as easily as a semiconductor device and provides the full functionality of a desk top computer. As is described in greater detail below, the same concepts of using a chip-like module using a QFP package with gull wing pins and having an ISA compatible bus is extended also to peripheral controller modules.

By integrating a full X86 AT-compatible computer onto a proprietary OEM design, the need for multiple boards is eliminated, thereby eliminating cables and mounting hardware.

The full compatibility with PC-AT ISA allows for easy integration with low-cost hardware peripherals. The ISA, compliant bus makes it easy to interface with proprietary hardware design.

One embodiment of the module 10, having a CPU as one of its functional circuits, is illustrated in FIG. 3 and includes the standard I/O interfaces, serial ports, a parallel port, and floppy and hard disk interfaces allowing standard hardware, cables, and software libraries to be incorporated in the design. The module 10 includes an 80386 SX CPU 20 which is connected to a DRAM bus 22 and an ISA bus 24 by means of core logic 26. The core logic controls AT-compatible DMA controllers, interrupt controllers, and timers/counters. It also controls the AT keyboard controller 28 and the real time clock 30. Two serial ports 32, 34 and a parallel port 36 are provided, as are a floppy disk controller 40 and an IDE hard drive interface 42. In order to facilitate total solid state operation, internal flash memory 44 is provided that is controlled by a solid state flash disk controller 46. Power is controlled by means of a power monitor 48 that provides a power saving function by controlling CPU sleep modes, and by a watch dog timer 50. The watch dog timer 50 monitors CPU cycles to detect interrupts in the cycle thereby allowing the system to be automatically reset after a predetermined time delay.

The microprocessor and various controllers and interfaces comprise chips, optionally in die form, mounted on a multi-layer PC board, e.g. ten-layers. The CPU 20 can be a standard 33 MHz 80386 SX CPU having a DRAM controller for supporting up to 16 M bytes of DRAM. Alternatively, CPU20 can be another standard microprocessor chip such as another type of 80386 chip or die, a 80486 chip or die, a Pentium chip or die, or any other desired microprocessor which is capable of providing the function of the 80386 device.

The standard DRAM interface provides all the signals for connecting standard page-mode DRAMs of various configurations, including standard 8- and 9-bit 30-pin SIMM modules and discrete components, such as standard 1 M×4 and 4 M×4 DRAM chips. The interface is designed to support 70 ns or faster DRAMs.

The DRAM interface consists of:

Multiplexed addresses MA00-MA10

Bi-directional data D0-D15

Column Address Strobes CASL0- to CASL3- (low byte)

CASH0- to CASH3- (high byte)

Row Address Strobes RAS0- to RAS3-

Memory Write Strobe DRWE-

The serial ports 32, 34 are PC-compatible asynchronous serial ports, typically treated as COM 1 and COM 2 devices by DOS.

    ______________________________________                                         Serial     Typical I/O           Standard                                      Port       Usage   Address       Interrupt                                     ______________________________________                                         Serial 1   COM1    3F8-3FF       IRQ4                                          Serial 2   COM2    2F8-2FF       IRQ3                                          ______________________________________                                    

Either or both serial ports can be disabled using SETUP. When disabled, the port*s I/O address and interrupt are made available for other expansion devices on the PC bus.

A full complement of input and output handshaking lines are supported by the serial ports, and all serial port signals are at standard LSTTL levels. In another embodiment, RS232C signal compatibility can be achieved by including a TTL-RS232C level converter to provide the necessary bipolar signal levels. The parallel port is a fully-compatible PC/AT parallel port providing bi-directional operation. It is typically used to support a line printer. As appears from the table below:

    ______________________________________                                         Parallel    Typical I/O           Standard                                     Port        Usage   Address       Interrupt                                    ______________________________________                                         Parallel 1  LPT1    378H-37FH     IRQ7                                         ______________________________________                                    

4.7K-ohm pull-ups (+5V) are typically provided to the following parallel port signals:

STROBE-

SLIN-

INIT-

AUTOFD-

Generally, if the parallel port will be connected to a cable for high speed data communication (as opposed to static digital output levels or static TTL level sensing), certain signals require a 2.2 nF capacitor connected to ground.

These include:

PD0-PD7

STRB-

Parallel port registers are provided for the parallel port as appears from the table set out below:

    ______________________________________                                         Parallel Port Registers                                                                                                 D                                                                              B2                                                                             5F                                                    Signal            Active Pi                                    Register                                                                               Bit     Name       In/Out High/Low                                                                              n                                     ______________________________________                                         DATA    0       PD0        I/O    HIGH    2                                    (A + 0) 1       PD1        I/O    HIGH    3                                            2       PD2        I/O    HIGH    4                                            3       PD3        I/O    HIGH    5                                            4       PD4        I/O    HIGH    6                                            5       PD5        I/O    HIGH    7                                            6       PD6        I/O    HIGH    8                                            7       PD7        I/O    HIGH    9                                    STATUS  0       1          --     --     --                                    (A + 1))                                                                               1       1          --     --     --                                            2       1          --     --     --                                            3       ERROR-     IN     LOW    15                                            4       SLCT-      IN     HIGH   13                                            5       PE         IN     HIGH   12                                            6       ACK-       IN     HIGH   10                                            7       BUSY       IN     LOW    11                                    CONTROL 0       STRB-      OUT    LOW     1                                    (A + 2) 1       AUTOFD-    OUT    LOW    14                                            2       INIT-      OUT    HIGH   16                                            3       SLCTIN-    OUT    LOW    17                                            4       IRQ ENABLE --     HIGH   --                                            5       1          --     --     --                                            6       1          --     --     --                                            7       1          --     --     --                                    ______________________________________                                    

The DOS-compatible floppy drive interface 40 allows cable connections for up to four floppy drives. In PC-compatible systems, the BIOS and DOS support two drives. These are configured using the BIOS SETUP function. Hardware controls for two additional drives are provided.

The floppy drive interface supports the following standard floppy formats:

    ______________________________________                                         Capacity  Drive Size   Tracks  Data Rate                                       ______________________________________                                         360K      51/4 inch    40      250 KHz                                         1.2M      51/4 inch    80      500 KHz                                         720K      31/2 inch    80      250 KHz                                         1.44M     31/2 inch    80      500 KHz                                         ______________________________________                                    

The various floppy interface resources are given in the table below

    ______________________________________                                         Floppy Interface Resources                                                     Resource     Function                                                          ______________________________________                                         I/O Address  3F2 FDC Digital Output Register (LDOR)                            3F0h-3F7h    3F4 FDC Main Status Register                                                   3F5 FDC Data Register                                                          3F7 FDC Control Register (LDCR)                                   IRQ6         Interrupt                                                         DRQ2BDACK2   DMA Controller Channel                                            ______________________________________                                    

Outputs to the floppy drive and from the floppy drive are Aopen collector=. Pull-up resistors are therefore required for proper termination, both on the SMX/386 board and on one of the attached floppy drives (not both).

330-Ohm pull-ups are required for the following floppy interface signals:

DSKCHG-

RDATA-

WRPRT-

TRK0-

INDEX-

The pin numbers and functions associated with the floppy drive are given in the table below:

    ______________________________________                                         Floppy Drive Interface                                                               Floppy                                                                   Pin   Pin       Signal Name                                                                               Function   In/Out                                   ______________________________________                                         11     2        DENSEL     Speed/Precomp                                              4        N/A                   N/A                                             6        N/S        Key pin    N/A                                      12     8        INDEX-     Index Pulse                                                                               IN                                       13    10        MTR0-      Motor On 0 OUT                                      15    12        DRV1-      Drive Select 2                                                                            OUT                                      18    14        DRV0-      Drive Select 1                                                                            OUT                                      20    16        MTR1-      Motor On 1 OUT                                      22    18        DIR-       Direction Select                                                                          OUT                                      23    20        STEP-      Step Pulse OUT                                      24    22        WDATA-     Write Data OUT                                      25    24        WGATE-     Write Gate OUT                                      26    26        TRK0-      Track 0    INPUT                                    27    28        WRPRT-     Write Protect                                                                             INPUT                                    28    30        RDATA-     Read Data  INPUT                                    29    32        HDSEL-     Head Select                                                                               OUT                                      30    34        DSKCHG-    Disk Change                                                                               INPUT                                          1B33      Ground     Ground                                              ______________________________________                                    

The IDE hard drive interface 42 is a standard interface used in PC-compatible systems for hard disk drives. Up to two drives can be connected in a master-slave arrangement. The resources are depicted in the table below:

    ______________________________________                                         IDE Hard Disk Resources                                                        Resource           Function                                                    ______________________________________                                         I/O Address        Hard Disk Interface                                         1F0h-1F7h                                                                      IRQ14              Interrupt                                                   ______________________________________                                    

The IDE interface pins are arranged to easily attach to a male PC-mounted ribbon-cable connector, the IDE drives typically being attached to the drive interface using a 40-pin ribbon cable.

The pin configuration for the IDE interface is given in the table below:

    ______________________________________                                         IDE Drive Interface                                                                 IDE                                                                       Pin  Pin      Signal Name                                                                               Function     In/Out                                   ______________________________________                                         223   1       HDRESET-   Reset signal from host                                                                      OUT                                            2       GND        Ground       OUT                                      224   3       IDED07     Data bit 7   I/O                                      225   4       HDD08      Data bit 8   I/O                                      226   5       HDD06      Data bit 6   I/O                                      227   6       HDD09      Data bit 9   I/O                                      228   7       HDD05      Data bit 5   I/O                                      229   8       HDD10      Data bit 10  I/O                                      230   9       HDD04      Data bit 4   I/O                                      231  10       HDD11      Data bit 11  I/O                                      232  11       HDD03      Data bit 3   I/O                                      233  12       HDD12      Data bit 12  I/O                                      234  13       HDD02      Data bit 2   I/O                                      235  14       HDD13      Data bit 13  I/O                                      236  15       HDD01      Data bit 1   I/O                                      237  16       HDD14      Data bit 14  I/O                                      238  17       HDD00      Data bit 0   I/O                                      239  18       HDD15      Data bit 15  I/O                                           19       GND        Ground       OUT                                           20       KEY        Keyed pin    N/C                                           21       N/A        Reserved     N/C                                           22       GND        Ground       OUT                                      240  23       HDIOW-     Write strobe OUT                                           24       GND        Ground       OUT                                       1   25       HDIOR-     Read strobe  OUT                                           26       GND        Ground       OUT                                           27       RSVD       Reserved     N/C                                       2   28       HDALE      Address latch enable                                                                        OUT                                           29       RSVD       Reserved     N/C                                           30       GND        Ground       OUT                                      237  31       HDD14      Drive interrupt request                                                                     IN                                       ______________________________________                                    

One embodiment of the pin configuration for the module 10 as a whole is illustated in FIGS. 4A and 4B are given in the pin description table below:

    ______________________________________                                         Pin  Pin Name  Description            Type                                     ______________________________________                                          1   HDIOR-    IDE I/O Read, active low, Buffered version                                                            O24                                                     of IOR                                                           2   HDALE     IDE Address Latch Enable, active high.                                                                O24                                                     Buffered version of BALE                                         3   IRQ14     IDE Interrupt Request 14. For use with IDE                                                            I                                                       interface. Same signal appears on pin 90.                        4   IOCS16    IDE I/O Chip Select 16. A low requests a                                                              I                                                       16-bit transfer on the SA bus. Same signal                                     appears on pin 238. This one is used for the                                   IDE interface.                                                   5   HDA1      IDE Address 1. Buffered version of SA1.                                                               O24                                       6   HDA0      IDE Address 0. Buffered version of SA0                                                                O24                                       7   HDA2      IDE Address 2. Buffered version of SA2                                                                O24                                       8   HDCS-     IDE Chip Select. A low indicates that data                                                            O24                                                     being transferred to or from the IDE drive.                      9   FDCS-     Floppy disk Chip Select. A low indicates                                                              O24t                                                    data is being transferred to or from the                                       floppy disk.                                                     10  LEDIN     LED signal from IDE drive                                                                             I                                         11  DENSEL                                                                     12  INDEX-    Floppy disk index pulse, input from drive                                                             I                                         13  MTR0-     Floppy disk active lower open drain output                                     selects motor driver 0. The motor enable                                       bits are software controlled via the                                           floppy's Digital Output Register (DOR).                          14  MTR2-     Floppy disk active low open drain output                                       selects motor driver 2. The motor enable                                       bits are software controlled via the                                           floppy's Digital Output Register (DOR).                          15  DRV1-     Floppy disk active lower open drain output                                     that selects floppy drive 1                                      16  DRV3-     Floppy disk active low open drain output                                       that selects floppy drive 3                                      17  GND                                                                        18  DRV0-     Floppy disk active low open drain output                                       that selects floppy drive 0                                      19  DRV2-     Floppy disk active low open drain output                                       that selects floppy drive 2                                      20  MTR1-     Floppy disk active low open drain output                                       selects motor driver 1. The motor enable bits                                  are software controlled via the floppy's                                       Digital Output Register (DOR).                                   21  MTR3-     Floppy disk active low open drain output                                       selects motor driver 3. The motor enable bits                                  are software controlled via the floppy's                                       Digital Output Register (DOR).                                   22  DIR       Floppy disk open drain output that controls                                    floppy read/write head movement direction.                                     Low=set pin.                                                     23  STEP-     Floppy disk active low output provides the                                     step pulse to move the floppy read/write                                       head                                                             24  WDATA-    Floppy disk active lower signal writes                                         precompensated serial data to the selected                                     floppy drive. This is a high open current                                      drain output and is gated internally with                                      WGATE-.                                                          25  WGATE-    Floppy disk active low open drain signal                                       that enables the head to write onto the                                        floppy disk.                                                     26  TRK0-     Floppy disk active lower Schmitt input                                                                IS                                                      indicates that the head is on track 0 of                                       the selected drive                                               27  WRPRT-    Floppy disk active low Schmitt input                                                                  IS                                                      indicating that the disk is write protected.                                   Any WDATA- command is ignored.                                   28  RDATA-    Floppy disk active lower Schmitt input that                                                           IS                                                      reads raw data from the floppy disk.                             29  HDSEL     Floppy disk open drain output that selects the                                 head on the selected drive. Low=side 0.                          30  DSKCHG    Floppy disk input signal indicating that                                                              Ihe                                                     floppy door has been opened.                                     31  5VBB                                                                       32  GND                                                                        33  PFI       Powerfail                                                        34  PFO       Powerfail                                                        35  MR-       Powerfail                                                        36  RTCIRQ-   Alarm output from the onboard real time                                        clock                                                            37  WDO       Watchdog timer                                                   38  SA00      ISA System Address 00  O24                                       39  OSC       ISA 14.318 MHz clock. This clock is                                            asynchronous to all other system clocks                          40  SA01      ISA System Address 01  O24                                       41  SA02      ISA System Address 02  O24                                       42  BALE      ISA Buffered Address Latch Enable                                43  SA03      ISA System Address 03  O24                                       44  SD15      ISA System Data 15                                               45  TC        ISA DMA Terminal Court                                           46  SA04      ISA System Address 04  O24                                       47  MASTER-   ISA                                                              48  SD14      ISA System Data 14                                               49  DACK2-    ISA DMA 2 Acknowledge strobe                                     50  SA05      ISA System Address 05  O24                                       51  SD13      ISA System Data 13                                               52  IRQ3      ISA Interrupt Request 3                                                                               I                                         53  SA06      ISA System Address 06  O24                                       54  DRQ7      ISA DMA 7 Request      I                                         55  SD12      ISA System Data 12                                               56  IRQ4      ISA Interrupt Request 4                                                                               I                                         57  SA07      ISA System Address 07  O24                                       58  DACK7-    ISA DMA 7 Acknowledge strobe                                     59  SD11      ISA System Data 11                                               60  IRQ5      ISA Interrupt Request 5                                                                               I                                         61  SA08      ISA System Address 08  O24                                       62  DRQ6      ISA DMA 6 Request      I                                         63  SD10      ISA System Data 10                                               64  IRQ6OUT   Floppy disk interrupt request. Normally                                        connects to IRQ6 (pin 65)                                        65  IRQ6      ISA Interrupt Request 6                                                                               I                                         66  SA09      ISA System Address 09  O24                                       67  GND                                                                        68  DACK6-    ISA DMA 6 Acknowledge strobe                                     69  SD09      ISA System Data 09                                               70  IRQ7OUT   Parallel port interrupt request. Normally                                      connects to IRQ7 (pin 71).                                       71  IRQ7      ISA Interrupt Request 7                                                                               I                                         72  SA10      ISA System Address 10  O24                                       73  DRQ5      ISA DMA 5 Request      I                                         74  SD08      ISA System Data 08                                               75  SYSCLK    ISA System Clock                                                 76  SA11      ISA System Address 11  O24                                       77  DACK5-    ISA DMA 5 Acknowledge strobe                                     78  MEMW-     ISA active low memory write strobe                               79  REFRESH-  ISA active low signal indicating current bus                                   cycle is a memory refresh                                        80  SA12      ISA System Address 12  O24                                       81  DRQ0      ISA DMA 0 Request      I                                         82  MEMR-     ISA active low memory read strobe                                83  DRQ1      ISA DMA 1 Request      I                                         84  SA13      ISA System Address 13  O24                                       85  VCC                                                                        86  DACK0-    ISA DSMA 0 Acknowledge strobe                                    87  LA17      ISA Latched Address 17 O24                                       88  DACK1-    ISA DMA 1 Acknowledge strobe                                     89  SA14      ISA System Address 14  O24                                       90  IRQ14     ISA Interrupt Request 14, normally used                                                               I                                                       for IDE interface                                                91  LA18      ISA Latched address 18 O24                                       92  DRQ3      ISA DMA 3 Request strobe                                         93  SA15      ISA System Address 15  O24                                       94  IRQ15     ISA Interrupt Request 15                                                                              I                                         95  LA19      ISA Latched Address 19 O24                                       96  DACK3-    ISA DMA 3 Acknowledge strobe                                     97  SA16      ISA System Address 16  O24                                       98  IRQ12     ISA Interrupt Request 12                                                                              I                                         99  LA20      ISA Latched Address 20 O24                                      100  IOR-      ISA I/O Read strobe                                             101  SA17      ISA System Address 17  O24                                      102  GND                                                                       103  IRQ11     ISA Interrupt Request 11                                                                              I                                        104  LA21      ISA Latched Address 21 O24                                      105  IOW-      ISA I/O Write strobe                                            106  SA18      ISA System Address 18  O24                                      107  IRQ10     ISA Interrupt Request 10                                                                              I                                        108  LA22      ISA Latched Address 22 O24                                      109  SMEMR-    ISA System Memory Read strobe                                   110  SA19      ISA System Address 19  O24                                      111  IOCS16-   ISA 16-bit I/O Chip Select request. Indicates                                                         I                                                       that the current I/O transaction is 16-bits.                    112  LA23      ISA Latched Address 23 O24                                      113  SMEMW-    ISA System Memory Write strobe                                  114  AEN       ISA Address Enable                                              115  MEMCS16-  ISA 16-bit Memory Chip Select request.                                                                I                                                       Indicates that the current memory transaction                                  is 16-bits.                                                     116  SBHE-     ISA System Byte High Enable                                     117  IOCHRDY   ISA I/O Channel Ready. A low adds wait                                                                I                                                       states to the current ISA bus cycle                             118  SD00      ISA System Data 00                                              119  OWS       ISA active low causing current memory                                                                 I                                                       cycle to be completed without additional                                       wait states.                                                    120  SD01      ISA System Data 01                                              121  SD02      ISA System Data 02                                              122  DRQ2OUT   Floppy DMA 2 Request. Normally                                                 connected to DRQ2 (pin 123)                                     123  DRQ2      ISA DMA 2 Request strobe                                                                              I                                        124  SD03      ISA System Data 03                                              125  SD04      ISA System Data 04                                              126  IRQ9      ISA Interrupt Request 09                                                                              I                                        127  SD05      ISA System Data 05                                              128  SD06      ISA System Data 06                                              129  RESETDR   ISA active high system reset signal                                  V                                                                         130  SD07      ISA System Data 07                                              131  IOCHCHK-  ISA gated non-maskable interrupt input                                                                I                                        132  HISPEED   Input to select CPU speed. High=high speed.                                                           I                                        133  SPKR      Speaker output                                                  134  KDATA     Keyboard data                                                   135  KCLOCK    Keyboard clock                                                  136  PWRDN-                                                                    137  GND                                                                       138  COLOR     Video Color/Mono jumper                                                                               I                                        139  KBLOCK    Keyboard lock. Low blocks keyboard input                                                              I                                        140  SLCT      Parallel Port                                                   141  PE        Parallel Port                                                   142  BUSY      Parallel Port                                                   143  ACK-      Parallel Port                                                   144  PD7       Parallel Port Data 7                                            145  PD6       Parallel Port Data 6                                            146  PD5       Parallel Port Data 5                                            147  PD4       Parallel Port Data 4                                            148  PD3       Parallel Port Data 3                                            149  SLCTIN-   Parallel Port                                                   150  PD2       Parallel Port Data 2                                            151  INIT-     Parallel Port                                                   152  PD1       Parallel Port Data 1                                            153  ERR-      Parallel Port                                                   154  GND                                                                       155  PD0       Parallel Port Data 0                                            156  AUTOFD    Parallel Port                                                   157  STRB-     Parallel Port                                                   158  DCD2      Serial Port 2 Data Carrier Detect                               159  DSR2      Serial Port 2 Data Set Ready                                    160  RXD2      Serial Port 2 Receive Data                                      161  RTS2      Serial Port 2 Request To Send                                   162  TXD2      Serial Port 2 Transmit Data                                     163  CTS2      Serial Port 2 Clear To Send                                     164  DTR2      Serial Port 2 Data Terminal Ready                               165  R12       Serial Port 2 Ring Indicator                                    166  DCD1      Serial Port 1 Data Carrier Detect                               167  DSR1      Serial Port 1 Data Set Ready                                    168  RXD1      Serial Port 1 Receive Data                                      169  RTS1      Serial Port 1 Request to Send                                   170  TXD1      Serial Port 1 Transmit Data                                     171  CTS1      Serial Port 1 Clear to Send                                     172  DTR1      Serial Port 1 Data Terminal Ready                               173  RI1       Serial Port 1 Ring Indicator                                    174  GAMECS                                                                    175  RAS3-     DRAM Row Address Strobe 3                                       176  RAS2-     DRAM Row Address Strobe 2                                       177  RAS1-     DRAM Row Address Strobe 1                                       178  RAS0-     DRAM Row Address Strobe 0                                       179  DP1       DRAM parity bit for high byte memory                            180  DP0       DRAM parity bit for low byte memory                             181  D15       DRAM Data Bit 15                                                182  D07       DRAM Data Bit 7                                                 183  D14       DRAM Data Bit 14                                                184  D06       DRAm Data Bit 6                                                 185  DRWE-     DRAM memory write strobe                                        186  D13       DRAM Data Bit 13                                                187  GND                                                                       188  D05       DRAM Data Bit 5                                                 189  MA10      DRAM multiplexed memory address 10                              190  MA09      DRAM multiplexed memory address 9                               191  MA08      DRAM multiplexed memory address 8                               192  D12       DRAM Data Bit 12                                                193  D04       DRAM Data Bit 4                                                 194  MA07      DRAM multiplexed memory address 7                               195  MA06      DRAM multiplexed memory address 6                               196  D11       DRAM Data Bit 11                                                197  D03       DRAM Data Bit 3                                                 198  MA05      DRAM multiplexed memory address 5                               199  MA04      DRAM multiplexed memory address 4                               200  D10       DRAM Data Bit 10                                                201  D01       DRAM Data Bit 2                                                 202  MA03      DRAM multiplexed memory address 3                               203  MA02      DRAM multiplexed memory address 2                               204  D09       DRAM Data Bit 9                                                 205  VCC                                                                       206  D01       DRAM Data Bit 1                                                 207  MA01      DRAM multiplexed memory address 1                               208  MA00      DRAM multiplexed memory address 0                               209  D08       DRAM Data Bit 8                                                 210  D00       DRAM Data Bit 0                                                 211  CASH3-    DRAM Column Address Strobe, High byte 3                         212  CASL3-    DRAM Column Address Strobe, Low byte 3                          213  CASH2-    DRAM Column Address Strobe, High byte 2                         214  CASL2-    DRAM Column Address Strobe, Low byte 2                          215  CASH1-    DRAM Column Address Strobe, High byte 1                         216  CASL1-    DRAM Column Address Strobe, Low byte 1                          217  CASH0-    DRAM Column Address Strobe, High byte 0                         218  CASL0-    DRAM Column Address Strobe, Low byte 0                          219  BDIS                                                                      220  XROMCS-                                                                   221  LEDOUT-                                                                   222  GND                                                                       223  HDRESET-  IDE                                                             224  IDED07    IDE Data Bit 7                                                  225  HDD08     IDE Data Bit 8                                                  226  HDD06     IDE Data Bit 6                                                  227  HDD09     IDE Data Bit 9                                                  228  HDD05     IDE Data Bit 5                                                  229  HDD10     IDE Data Bit 10                                                 230  HDD04     IDE Data Bit 4                                                  231  HDD11     IDE Data Bit 11                                                 232  HDD03     IDE Data Bit 3                                                  233  HDD12     IDE Data Bit 12                                                 234  HDD02     IDE Data Bit 2                                                  235  HDD13     IDE Data Bit 13                                                 236  HDD01     IDE Data Bit 1                                                  237  HDD14     IDE Data Bit 14                                                 238  HDD00     IDE Data Bit 0                                                  239  HDD15     IDE Data Bit 15                                                 240  HDIOW-    IDE buffered I/O Write strobe                                   ______________________________________                                    

As mentioned above, the core logic 26 supports a DRAM bus 22 and an ISA compatible expansion bus 24 complying in number and signal type with the IEEE-P996 requirements (and corresponding to the ISA (Industry Standard Architecture) requirements). The pin configuration for the expansion bus 24 is given in the table below with corresponding pin numbers for expansion bus connectors A, B, C, D. The bus 24 comprises 94 pins that includes VCC and two GND pins.

    ______________________________________                                                                          In/  Cur-                                          Pin    Signal Name                                                                              Function   Out  rent Load*                               ______________________________________                                         38   A31    SA00      Address bit 0                                                                             I/O  12   PU                                                                        mA                                       39   B30    OSC       14.318 MHz clock                                                                          Out  6 mA 33 SER                              40   A30    SA01      Address bit 1                                                                             I/O  12   PU                                                                        mA                                       41   A29    SA02      Address bit 2                                                                             I/O  12   PU                                                                        mA                                       42   B28    BALE      Address latch enable                                                                      Out  12                                                                             mA                                       43   A28    SA03      Address bit 3                                                                             I/O  12   PU                                                                        mA                                       44   C18    SD15      System Data bit 15                                                                        I/O  12   PU                                                                        mA                                       45   B27    TC        DMA Terminal                                                                              Out  4 mA                                                           Count                                                    46   A27    SA04      Address bit 4                                                                             I/O  12   PU                                                                        mA                                       47   D17    MASTER-   Bus master assert                                                                         In   N/A  330 PU                              48   C17    SD14      System Data bit 14                                                                        I/O  24   PU                                                                        mA                                       49   B26    DACK2-    DMA Acknowledge                                                                           Out  4 mA                                                           2                                                        50   A26    SA05      Address bit 5                                                                             I/O  12   PU                                                                        mA                                       51   C16    SD13      System Data bit 13                                                                        I/O  24   PU                                                                        mA                                       52   B25    IRQ3      Interrupt Request 3                                                                       In   N/A  PU                                  53   A25    SA06      Address bit 6                                                                             I/O  12   PU                                                                        mA                                       54   D15    DRQ7      DMA Request 7                                                                             In   N/A  PD                                  55   C15    SD12      System Data bit 12                                                                        I/O  24   PU                                                                        mA                                       56   B24    IRQ4      Interrupt Request 4                                                                       In   N/A  PU                                  57   A24    SA07      Address bit 7                                                                             I/O  12   PU                                                                        mA                                       58   D14    DACK7-    DMA Acknowledge                                                                           Out  4 mA                                                           7                                                        59   C14    SD11      System Data bit 11                                                                        I/O  24   PU                                                                        mA                                       60   B23    IRQ5      Interrupt Request 5                                                                       In   N/A  PU                                  61   A23    SA08      Address bit 8                                                                             I/O  12   PU                                                                        mA                                       62   D13    DRQ6      DMA Request 6                                                                             In   N/A  PD                                  63   C13    SD10      System Data bit 10                                                                        I/O  24   PU                                                                        mA                                       64          IRQ6OUT   Floppy Disk                                                                    Interrupt Request                                        65   B22    IRQ6      Interrupt Request 6                                                                       In   N/A  PU                                  66   A22    SA09      Address bit 9                                                                             I/O  12   PU                                                                        mA                                       67          GND                                                                68   D12    DACK6-    DMA Acknowledge                                                                           Out  4 mA                                                           6                                                        69   C12    SD9       System Data bit 9                                                                         I/O  24   PU                                                                        mA                                       70          IRQ7OUT   Parallel Port                                                                  Interrupt Request                                        71   B21    IRQ7      Interrupt Request 7                                                                       In   N/A  PU                                  72   A21    SA10      Address bit 10                                                                            I/O  12   PU                                                                        mA                                       73   D11    DRQ5      DMA Request 5                                                                             In   N/A  PD                                  74   C11    SD08      System Data bit 8                                                                         I/O  24   PU                                                                        mA                                       75   B20    SYSCLK    System clock (8                                                                           Out  12                                                             MHz)            mA                                       76   A20    SA11      Address bit 11                                                                            I/O  12   PU                                                                        mA                                       77   D10    DACK5-    DMA Acknowledge                                                                           Out  4 mA                                                           5                                                        78   C10    MEMW-     Memory Write                                                                              I/O  6 mA PU, 33                                                                         SER                                 79   B19    REFRESH-  Memory Refresh                                                                            I/O  6 mA 470 PU,                                                                        33 SER                              80   A19    SA12      Address bit 12                                                                            I/O  12   PU                                                                        mA                                       81   D9     DRQ0      DMA Request 0                                                                             In   N/A  PD                                  82   C9     MEMR-     Memory Read                                                                               I/O  6 mA PU, 33                                                                         SER                                 83   B18    DRQ1      DMA Request 1                                                                             In   N/A  PD                                  84   A18    SA13      Address bit 13                                                                            I/O  12   PU                                                                        mA                                       85          VCC                                                                86   D8     DACK0-    DMA Acknowledge                                                                           Out  4 mA                                                           0                                                        87   C8     LA17      Address bit 17                                                                            I/O  24                                                                             mA                                       88   B17    DACK1-    DMA Acknowledge                                                                           Out  4 mA                                                           1                                                        89   A17    SA14      Address bit 14                                                                            I/O  12   PU                                                                        mA                                       90   D7     IRQ14     Interrupt Request 14                                                                      In   N/A  PU                                  91   C7     LA18      Address bit 18                                                                            I/O  24                                                                             mA                                       92   B16    DRQ3      DMA Request 3                                                                             In   N/A  PD                                  93   A16    SA15      Address bit 15                                                                            I/O  12   PU                                                                        mA                                       94   D6     IRQ15     Interrupt Request 15                                                                      In   N/A  PU                                  95   C6     LA19      Address bit 19                                                                            I/O  24                                                                             mA                                       96   B15    DACK3-    DMA Acknowledge                                                                           Out  4 mA                                                           3                                                        97   A15    SA16      Address bit 16                                                                            I/O  12   PU                                                                        mA                                       98   D5     IRQ12     Interrupt Request 12                                                                      In   N/A  PU                                  99   C5     LA20      Address bit 20                                                                            I/O  24                                                                             mA                                       100  B14    IOR-      I/O Read   I/O  6 mA PU                                  101  A14    SA17      Address bit 17                                                                            I/O  12   PU                                  102         GND                       mA                                       103  D4     IRQ11     Interrupt Request 11                                                                      In   N/A  PU                                  104  C4     LA21      Address bit 21                                                                            I/O  24                                                                             mA                                       105  B13    IOW-      I/O Write  I/O  6 mA PU                                  106  A13    SA18      Address bit 18                                                                            I/O  12   PU                                                                        mA                                       107  D3     IRQ10     Interrupt Request 10                                                                      In   N/A  PU                                  108  C3     LA22      Address bit 22                                                                            I/O  24                                                                             mA                                       109  B12    SMEMR-    Mem Read (lower                                                                           I/O  6 mA 33 SER                                                    IMB)                                                     110  A12    SA19      Address bit 19                                                                            I/O  12   PU                                                                        mA                                       111  D2     IOCS16-   16-bit I/O access                                                                         In   N/A  330 PU                              112  C2     LA23      Address bit 23                                                                            I/O  24                                                                             mA                                       113  B11    SMEMW-    Mem Write (lower 1                                                                        I/O  6 mA 33 SER                                                    MB)                                                      114  A11    AEN       Address Enable                                                                            I/O  12   PU                                                                        mA                                       115  D1     MEMCS16-  16-bit mem access                                                                         In   N/A  330 PU                              116  C1     SBHE-     Bus High Enable                                                                           I/O  12   PU                                                                        mA                                       117  A10    IOCHRDY   Processor Ready                                                                           In   N/A  1K PU                                                     Ctrl                                                     118  A9     SD00      System Data bit 0                                                                         I/O  24   PU                                                                        mA                                       119  B8     ENDXFR-   Zero wait state                                                                           In   N/A  330 PU                                          (OWS-)                                                             120  A8     SD01      System Data bit 1                                                                         I/O  24   PU                                                                        mA                                       121  A7     SD02      System Data bit 2                                                                         I/O  24   PU                                                                        mA                                       122         DRQ2OUT   Floppy DMA 2                                                                   Request                                                  123  B6     DRQ2      DMA request 2                                                                             In   N/A  PD                                  124  A6     SD03      System Data bit 3                                                                         I/O  24   PU                                                                        mA                                       125  A5     SD04      System Data bit 4                                                                         I/O  24   PU                                                                        mA                                       126  B4     IRQ9      Interrupt request 9                                                                       In   N/A  PU                                  127  A4     SD05      System Data bit 5                                                                         I/O  24   PU                                                                        mA                                       128  A4     SD06      System Data bit 6                                                                         I/O  24   PU                                                                        mA                                       129  B2     RESETDRV  System reset signal                                                                       Out  24                                                                             mA                                       130  A2     SD07      System Data bit 7                                                                         I/O  24   PU                                                                        mA                                       131  A1     IOCHCK-   Sub NMI input                                                                             In   N/A  4.7K                                                                           PU                                  ______________________________________                                    

An alternative embodiment of the pin configuration for the module 10 as a whole is rated in FIGS. 5A and 5B are given in the pin description table below:

    ______________________________________                                         Pin  Pin Name  Description            Type                                     ______________________________________                                          1   HDIOR-    IDE I/O Read, active low, Buffered version                                                            O24                                                     of IOR                                                           2   HDALE     IDE Address Latch Enable, active high.                                                                O24                                                     Buffered version of BALE                                         3   IRQ14     IDE Interrupt Request 14. For use with IDE                                                            I                                                       interface. Same signal appears on pin 90.                        4   IOCS16-   IDE I/O Chip Select 16. A low requests a                                                              I                                                       16-bit transfer on the SA bus. Same signal                                     appears on pin 238. This one is used for the                                   IDE interface.                                                   5   HDA1      IDE Address 1. Buffered version of SA1.                                                               O24                                       6   HDA0      IDE Address 0. Buffered version of SA0                                                                O24                                       7   HDA2      IDE Address 2. Buffered version of SA2                                                                O24                                       8   HDCS-     IDE Chip Select. A low indicates that data                                                            O24                                                     being transferred to or from the IDE drive.                      9   FDCS-     Floppy disk Chip Select. A low indicates                                                              O24t                                                    data is being transferred to or from the                                       floppy disk.                                                     10  LEDIN     LED signal from IDE drive                                                                             I                                         11  DENSEL                                                                     12  INDEX-    Floppy disk index pulse, input from drive                                                             I                                         13  MTR0-     Floppy disk active lower open drain output                                     selects motor driver 0. The motor enable                                       bits are software controlled via the                                           floppy's Digital Output Register (DOR).                          14  MTR2-     Floppy disk active low open drain output                                       selects motor driver 2. The motor enable                                       bits are software controlled via the                                           floppy's Digital Output Register (DOR).                          15  DRV1-     Floppy disk active lower open drain output                                     that selects floppy drive 1                                      16  DRV3-     Floppy disk active low open drain output                                       that selects floppy drive 3                                      17  GND                                                                        18  DRV0-     Floppy disk active low open drain output                                       that selects floppy drive 0                                      19  DRV2-     Floppy disk active low open drain output                                       that selects floppy drive 2                                      20  MTR1-     Floppy disk active low open drain output                                       selects motor driver 1. The motor enable bits                                  are software controlled via the floppy's                                       Digital Output Register (DOR).                                   21  MTR3-     Floppy disk active low open drain output                                       selects motor driver 3. The motor enable bits                                  are software controlled via the floppy's                                       Digital Output Register (DOR).                                   22  DIR       Floppy disk open drain output that controls                                    floppy read/write head movement direction.                                     Low=set pin.                                                     23  STEP-     Floppy disk active low output provides the                                     step pulse to move the floppy read/write                                       head                                                             24  WDATA-    Floppy disk active lower signal writes                                         precompensated serial data to the selected                                     floppy drive. This is a high open current                                      drain output and is gated internally with                                      WGATE-.                                                          25  WGATE-    Floppy disk active low open drain signal                                       that enables the head to write onto the                                        floppy disk.                                                     26  TRK0-     Floppy disk active lower Schmitt input                                                                IS                                                      indicates that the head is on track 0 of                                       the selected drive                                               27  WRPRT-    Floppy disk active low Schmitt input                                                                  IS                                                      indicating that the disk is write protected.                                   Any WDATA- command is ignored.                                   28  RDATA-    Floppy disk active lower Schmitt input that                                                           IS                                                      reads raw data from the floppy disk.                             29  HDSEL     Floppy disk open drain output that selects the                                 head on the selected drive. Low=side 0.                          30  DSKCHG    Floppy disk input signal indicating that                                                              Ihe                                                     floppy door has been opened.                                     31  5VBB                                                                       32  GND                                                                        33  PFI       Powerfail                                                        34  PFO       Powerfail                                                        35  MR-       Powerfail                                                        36  RTCIRQ-   Alarm output from the onboard real time                                        clock                                                            37  WDO       Watchdog timer                                                   38  IOCHCK    ISA System Address 00  O24                                       39  SD07      ISA 14.318 MHz clock. This clock is                                            asynchronous to all other system clocks                          40  RESETDRV  ISA System Address 01  O24                                       41  SD06      ISA System Address 02  O24                                       42  SD05      ISA Buffered Address Latch Enable                                43  IRQ9      ISA System Address 03  O24                                       44  SD04      ISA System Data 15                                               45  SD03      ISA DMA Terminal Court                                           46  DRQ2      ISA System Address 04  O24                                       47  DRQ2OUT-  ISA                                                              48  SD02      ISA System Data 14                                               49  SD01-     ISA DMA 2 Acknowledge strobe                                     50  OWS       ISA System Address 05  O24                                       51  SD00      ISA System Data 13                                               52  IOCHRDY   ISA Interrupt Request 3                                                                               I                                         53  SBHE-     ISA System Address 06  O24                                       54  MEMCS16-  ISA DMA 7 Request      I                                         55  AEN       ISA System Data 12                                               56  SMEMW-    ISA Interrupt Request 4                                                                               I                                         57  LA23      ISA System Address 07  O24                                       58  IOCS16-   ISA DMA 7 Acknowledge strobe                                     59  SA19      ISA System Data 11                                               60  SMEMR-    ISA Interrupt Request 5                                                                               I                                         61  LA22      ISA System Address 08  O24                                       62  IRQ10     ISA DMA 6 Request      I                                         63  SA18      ISA System Data 10                                               64  IOW-      Floppy disk interrupt request. Normally                                        connects to IRQ6 (pin 65)                                        65  LA21      ISA Interrupt Request 6                                                                               I                                         66  IRQ11     ISA System Address 09  O24                                       67  GND                                                                        68  SA17      ISA DMA 6 Acknowledge strobe                                     69  IOR-      ISA System Data 09                                               70  LA20      Parallel port interrupt request. Normally                                      connects to IRQ7 (pin 71).                                       71  IRQ12     ISA Interrupt Request 7                                                                               I                                         72  SA16      ISA System Address 10  O24                                       73  DACK3-    ISA DMA 5 Request      I                                         74  LA19      ISA System Data 08                                               75  IRQ15     ISA System Clock                                                 76  SA15      ISA System Address 11  O24                                       77  DRQ3      ISA DMA 5 Acknowledge strobe                                     78  LA18      ISA active low memory write strobe                               79  IRQ14     ISA active low signal indicating current bus                                   cycle is a memory refresh                                        80  SA14      ISA System Address 12  O24                                       81  DACK1-    ISA DMA 0 Request      I                                         82  LA17      ISA active low memory read strobe                                83  DACK0-    ISA DMA 1 Request      I                                         84  SA13      ISA System Address 13  O24                                       85  VCC                                                                        86  DRQ1-     ISA DSMA 0 Acknowledge strobe                                    87  MEMR-     ISA Latched Address 17 O24                                       88  DRQ0      ISA DMA 1 Acknowledge strobe                                     89  SA12      ISA System Address 14  O24                                       90  REFRESH-  ISA Interrupt Request 14, normally used                                                               I                                                       for IDE interface                                                91  MEMW-     ISA Latched address 18 O24                                       92  DACK5-    ISA DMA 3 Request strobe                                         93  SA11      ISA System Address 15  O24                                       94  SYSCLK    ISA Interrupt Request 15                                                                              I                                         95  SD08      ISA Latched Address 19 O24                                       96  DRQ5      ISA DMA 3 Acknowledge strobe                                     97  SA10      ISA System Address 16  O24                                       98  IRQ7      ISA Interrupt Request 12                                                                              I                                         99  IRQ7OUT   ISA Latched Address 20 O24                                      100  SD09      ISA I/O Read strobe                                             101  DACK6-    ISA System Address 17  O24                                      102  GND                                                                       103  SA09      ISA Interrupt Request 11                                                                              I                                        104  IRQ6      ISA Latched Address 21 O24                                      105  IRQ6OUT   ISA I/O Write strobe                                            106  SD10      ISA System Address 18  O24                                      107  DRQ6      ISA Interrupt Request 10                                                                              I                                        108  SA08      ISA Latched Address 22 O24                                      109  IRQ5      ISA System Memory Read strobe                                   110  SD11      ISA System Address 19  O24                                      111  DACK7-    ISA 16-bit I/O Chip Select request. Indicates                                                         I                                                       that the current I/O transaction is 16-bits.                    112  SA07      ISA Latched Address 23 O24                                      113  IRQ4      ISA System Memory Write strobe                                  114  SD12      ISA Address Enable                                              115  DRQ7      ISA 16-bit Memory Chip Select request.                                                                I                                                       Indicates that the current memory transaction                                  is 16-bits.                                                     116  SA06      ISA System Byte High Enable                                     117  IRQ3      ISA I/O Channel Ready. A low adds wait                                                                I                                                       states to the current ISA bus cycle                             118  SD13      ISA System Data 00                                              119  SA05      ISA active low causing current memory                                                                 I                                                       cycle to be completed without additional                                       wait states.                                                    120  DACK2-    ISA System Data 01                                              121  SD14      ISA System Data 02                                              122  MASTER-   Floppy DMA 2 Request. Normally                                                 connected to DRQ2 (pin 123)                                     123  SA04      ISA DMA 2 Request strobe                                                                              I                                        124  TC        ISA System Data 03                                              125  SD15      ISA System Data 04                                              126  SA03      ISA Interrupt Request 09                                                                              I                                        127  BALE      ISA System Data 05                                              128  SA02      ISA System Data 06                                              129  SA01      ISA active high system reset signal                             130  OSV       ISA System Data 07                                              131  SA00      ISA gated non-maskable interrupt input                                                                I                                        132  HISPEED   Input to select CPU speed. High=high speed.                                                           I                                        133  SPKR      Speaker output                                                  134  KDATA     Keyboard data                                                   135  KCLOCK    Keyboard clock                                                  136  PWRDN-                                                                    137  GND                                                                       138  COLOR     Video Color/Mono jumper                                                                               I                                        139  KBLOCK    Keyboard lock. Low blocks keyboard input                                                              I                                        140  SLCT      Parallel Port                                                   141  PE        Parallel Port                                                   142  BUSY      Parallel Port                                                   143  ACK-      Parallel Port                                                   144  PD7       Parallel Port Data 7                                            145  PD6       Parallel Port Data 6                                            146  PD5       Parallel Port Data 5                                            147  PD4       Parallel Port Data 4                                            148  PD3       Parallel Port Data 3                                            149  SLCTIN-   Parallel Port                                                   150  PD2       Parallel Port Data 2                                            151  INIT-     Parallel Port                                                   152  PD1       Parallel Port Data 1                                            153  ERR-      Parallel Port                                                   154  GND                                                                       155  PD0       Parallel Port Data 0                                            156  AUTOFD    Parallel Port                                                   157  STRB-     Parallel Port                                                   158  DCD2      Serial Port 2 Data Carrier Detect                               159  DSR2      Serial Port 2 Data Set Ready                                    160  RXD2      Serial Port 2 Receive Data                                      161  RTS2      Serial Port 2 Request To Send                                   162  TXD2      Serial Port 2 Transmit Data                                     163  CTS2      Serial Port 2 Clear To Send                                     164  DTR2      Serial Port 2 Data Terminal Ready                               165  R12       Serial Port 2 Ring Indicator                                    166  DCD1      Serial Port 1 Data Carrier Detect                               167  DSR1      Serial Port 1 Data Set Ready                                    168  RXD1      Serial Port 1 Receive Data                                      169  RTS1      Serial Port 1 Request to Send                                   170  TXD1      Serial Port 1 Transmit Data                                     171  CTS1      Serial Port 1 Clear to Send                                     172  DTR1      Serial Port 1 Data Terminal Ready                               173  RI1       Serial Port 1 Ring Indicator                                    174  GAMECS                                                                    175  RAS3-     DRAM Row Address Strobe 3                                       176  RAS2-     DRAM Row Address Strobe 2                                       177  RAS1-     DRAM Row Address Strobe 1                                       178  RAS0-     DRAM Row Address Strobe 0                                       179  DP1       DRAM parity bit for high byte memory                            180  DP0       DRAM parity bit for low byte memory                             181  D15       DRAM Data Bit 15                                                182  D07       DRAM Data Bit 7                                                 183  D14       DRAM Data Bit 14                                                184  D06       DRAm Data Bit 6                                                 185  DRWE-     DRAM memory write strobe                                        186  D13       DRAM Data Bit 13                                                187  GND                                                                       188  D05       DRAM Data Bit 5                                                 189  MA10      DRAM multiplexed memory address 10                              190  MA09      DRAM multiplexed memory address 9                               191  MA08      DRAM multiplexed memory address 8                               192  D12       DRAM Data Bit 12                                                193  D04       DRAM Data Bit 4                                                 194  MA07      DRAM multiplexed memory address 7                               195  MA06      DRAM multiplexed memory address 6                               196  D11       DRAM Data Bit 11                                                197  D03       DRAM Data Bit 3                                                 198  MA05      DRAM multiplexed memory address 5                               199  MA04      DRAM multiplexed memory address 4                               200  D10       DRAM Data Bit 10                                                201  D01       DRAM Data Bit 2                                                 202  MA03      DRAM multiplexed memory address 3                               203  MA02      DRAM multiplexed memory address 2                               204  D09       DRAM Data Bit 9                                                 205  VCC                                                                       206  D01       DRAM Data Bit 1                                                 207  MA01      DRAM multiplexed memory address 1                               208  MA00      DRAM multiplexed memory address 0                               209  D08       DRAM Data Bit 8                                                 210  D00       DRAM Data Bit 0                                                 211  CASH3-    DRAM Column Address Strobe, High byte 3                         212  CASL3-    DRAM Column Address Strobe, Low byte 3                          213  CASH2-    DRAM Column Address Strobe, High byte 2                         214  CASL2-    DRAM Column Address Strobe, Low byte 2                          215  CASH1-    DRAM Column Address Strobe, High byte 1                         216  CASL1-    DRAM Column Address Strobe, Low byte 1                          217  CASH0-    DRAM Column Address Strobe, High byte 0                         218  CASL0-    DRAM Column Address Strobe, Low byte 0                          219  BDIS                                                                      220  XROMCS-                                                                   221  LEDOUT-                                                                   222  GND                                                                       223  HDRESET-  IDE                                                             224  IDED07    IDE Data Bit 7                                                  225  HDD08     IDE Data Bit 8                                                  226  HDD06     IDE Data Bit 6                                                  227  HDD09     IDE Data Bit 9                                                  228  HDD05     IDE Data Bit 5                                                  229  HDD10     IDE Data Bit 10                                                 230  HDD04     IDE Data Bit 4                                                  231  HDD11     IDE Data Bit 11                                                 232  HDD03     IDE Data Bit 3                                                  233  HDD12     IDE Data Bit 12                                                 234  HDD02     IDE Data Bit 2                                                  235  HDD13     IDE Data Bit 13                                                 236  HDD01     IDE Data Bit 1                                                  237  HDD14     IDE Data Bit 14                                                 238  HDD00     IDE Data Bit 0                                                  239  HDD15     IDE Data Bit 15                                                 240  HDIOW-    IDE buffered I/O Write strobe                                   ______________________________________                                    

A second embodiment of the pin configuration for the expansion bus 24 is given in the table below with corresponding pin numbers for expansion bus connectors A, B, C, D. As mentioned before, bus 24 comprises 94 pins that includes VCC and two GND pins.

    ______________________________________                                                                          In/  Cur-                                          Pin    Signal Name                                                                              Function   Out  rent Load*                               ______________________________________                                         38   A31    IOCHCK    Address bit 0                                                                             I/O  12   PU                                                                        mA                                       39   B30    SD07      14.318 MHz clock                                                                          Out  6 mA 33 SER                              40   A30    RESETDR   Address bit 1                                                                             I/O  12   PU                                              V                         mA                                       41   A29    SD06      Address bit 2                                                                             I/O  12   PU                                                                        mA                                       42   B28    SD05      Address latch enable                                                                      Out  12                                                                             mA                                       43   A28    IRQ9      Address bit 3                                                                             I/O  12   PU                                                                        mA                                       44   C18    SD04      System Data bit 15                                                                        I/O  12   PU                                                                        mA                                       45   B27    SD03      DMA Terminal                                                                              Out  4 mA                                                           Count                                                    46   A27    DRQ2      Address bit 4                                                                             I/O  12   PU                                                                        mA                                       47   D17    DRQ2OUT   Bus master assert                                                                         In   N/A  330 PU                              48   C17    SD02      System Data bit 14                                                                        I/O  24   PU                                                                        mA                                       49   B26    SD01-     DMA Acknowledge                                                                           Out  4 mA                                                           2                                                        50   A26    0WS       Address bit 5                                                                             I/O  12   PU                                                                        mA                                       51   C16    SD00      System Data bit 13                                                                        I/O  24   PU                                                                        mA                                       52   B25    IOCHRDY   Interrupt Request 3                                                                       In   N/A  PU                                  53   A25    SBHE-     Address bit 6                                                                             I/O  12   PU                                                                        mA                                       54   D15    MEMCS 16- DMA Request 7                                                                             In   N/A  PD                                  55   C15    AEN       System Data bit 12                                                                        I/O  24   PU                                                                        mA                                       56   B24    SMEMW-    Interrupt Request 4                                                                       In   N/A  PU                                  57   A24    LA23      Address bit 7                                                                             I/O  12   PU                                                                        mA                                       58   D14    IOCS16-   DMA Acknowledge                                                                           Out  4 mA                                                           7                                                        59   C14    SA19      System Data bit 11                                                                        I/O  24   PU                                                                        mA                                       60   B23    SMEMR-    Interrupt Request 5                                                                       In   N/A  PU                                  61   A23    LA22      Address bit 8                                                                             I/O  12   PU                                                                        mA                                       62   D13    IRQ10     DMA Request 6                                                                             In   N/A  PD                                  63   C13    SA18      System Data bit 10                                                                        I/O  24   PU                                                                        mA                                       64          IOW-      Floppy Disk                                                                    Interrupt Request                                        65   B22    LA21      Interrupt Request 6                                                                       In   N/A  PU                                  66   A22    IRQ11     Address bit 9                                                                             I/O  12   PU                                                                        mA                                       67          GND                                                                68   D12    SA17      DMA Acknowledge                                                                           Out  4 mA                                                           6                                                        69   C12    IOR-      System Data bit 9                                                                         I/O  24   PU                                                                        mA                                       70          LA20      Parallel Port                                                                  Interrupt Request                                        71   B21    IRQ12     Interrupt Request 7                                                                       In   N/A  PU                                  72   A21    SA16      Address bit 10                                                                            I/O  12   PU                                                                        mA                                       73   D11    DACK3-    DMA Request 5                                                                             In   N/A  PD                                  74   C11    LA19      System Data bit 8                                                                         I/O  24   PU                                                                        mA                                       75   B20    IRQ15     System clock (8                                                                           Out  12                                                             MHz)            mA                                       76   A20    SA15      Address bit 11                                                                            I/O  12   PU                                                                        mA                                       77   D10    DRQ3      DMA Acknowledge                                                                           Out  4 mA                                                           5                                                        78   C10    LA18      Memory Write                                                                              I/O  6 mA PU, 33                                                                         SER                                 79   B19    IRQ14     Memory Refresh                                                                            I/O  6 mA 470 PU,                                                                        33 SER                              80   A19    SA14      Address bit 12                                                                            I/O  12   PU                                                                        mA                                       81   D9     DACK1-    DMA Request 0                                                                             In   N/A  PD                                  82   C9     LA17      Memory Read                                                                               I/O  6 mA PU, 33                                                                         SER                                 83   B18    DACK0-    DMA Request 1                                                                             In   N/A  PD                                  84   A18    SA13      Address bit 13                                                                            I/O  12   PU                                  85          VCC                       mA                                       86   D8     DRQ1-     DMA Acknowledge                                                                           Out  4 mA                                                           0                                                        87   C8     MEMR-     Address bit 17                                                                            I/O  24                                                                             mA                                       88   B17    DRQ0      DMA Acknowledge                                                                           Out  4 mA                                                           1                                                        89   A17    SA12      Address bit 14                                                                            I/O  12   PU                                                                        mA                                       90   D7     REFRESH-  Interrupt Request 14                                                                      In   N/A  PU                                  91   C7     MEMW-     Address bit 18                                                                            I/O  24                                                                             mA                                       92   B16    DACK5-    DMA Request 3                                                                             In   N/A  PD                                  93   A16    SA11      Address bit 15                                                                            I/O  12   PU                                                                        mA                                       94   D6     SYSCLK    Interrupt Request 15                                                                      In   N/A  PU                                  95   C6     SD08      Address bit 19                                                                            I/O  24                                                                             mA                                       96   B15    DRQ5      DMA Acknowledge                                                                           Out  4 mA                                                           3                                                        97   A15    SA10      Address bit 16                                                                            I/O  12   PU                                                                        mA                                       98   D5     IRQ7      Interrupt Request 12                                                                      In   N/A  PU                                  99   C5     IRQ7OUT   Address bit 20                                                                            I/O  24                                                                             mA                                       100  B14    SD09      I/O Read   I/O  6 mA PU                                  101  A14    DACK6-    Address bit 17                                                                            I/O  12   PU                                  102         GND                       mA                                       103  D4     SA09      Interrupt Request 11                                                                      In   N/A  PU                                  104  C4     IRQ6      Address bit 21                                                                            I/O  24                                                                             mA                                       105  B13    IRQ6OUT   I/O Write  I/O  6 mA PU                                  106  A13    SD10      Address bit 18                                                                            I/O  12   PU                                                                        mA                                       107  D3     DRQ6      Interrupt Request 10                                                                      In   N/A  PU                                  108  C3     SA08      Address bit 22                                                                            I/O  24                                                                             mA                                       109  B12    IRQ5      Mem Read (lower                                                                           I/O  6 mA 33 SER                                                    IMB)                                                     110  A12    SD11      Address bit 19                                                                            I/O  12   PU                                                                        mA                                       111  D2     DACK7-    16-bit I/O access                                                                         In   N/A  330 PU                              112  C2     SA07      Address bit 23                                                                            I/O  24                                                                             mA                                       113  B11    IRQ4      Mem Write (lower 1                                                                        I/O  6 mA 33 SER                                                    MB)                                                      114  A11    SD12      Address Enable                                                                            I/O  12   PU                                                                        mA                                       115  D1     DRQ7      16-bit mem access                                                                         In   N/A  330 PU                              116  C1     SA06      Bus High Enable                                                                           I/O  12   PU                                                                        mA                                       117  A10    IRQ3      Processor Ready                                                                           In   N/A  1K PU                                                     Ctrl                                                     118  A9     SD13      System Data bit 0                                                                         I/O  24   PU                                                                        mA                                       119  B8     SA05      Zero wait state                                                                           In   N/A  330 PU                              120  A8     DACK2-    System Data bit 1                                                                         I/O  24   PU                                                                        mA                                       121  A7     SD14      System Data bit 2                                                                         I/O  24   PU                                                                        mA                                       122         MASTER-   Floppy DMA 2                                                                   Request                                                  123  B6     SA04      DMA request 2                                                                             In   N/A  PD                                  124  A6     TC        System Data bit 3                                                                         I/O  24   PU                                                                        mA                                       125  A5     SD15      System Data bit 4                                                                         I/O  24   PU                                                                        mA                                       126  B4     SA03      Interrupt request 9                                                                       In   N/A  PU                                  127  A4     BALE      System Data bit 5                                                                         I/O  24   PU                                                                        mA                                       128  A4     SA02      System Data bit 6                                                                         I/O  24   PU                                                                        mA                                       129  B2     SA01      System reset signal                                                                       Out  24                                                                             mA                                       130  A2     OSC       System Data bit 7                                                                         I/O  24   PU                                                                        mA                                       131  A1     SA00      Sub NMI input                                                                             In   N/A  4.7K                                                                           PU                                  ______________________________________                                    

The exact pin configuration as illustrated for the expansion bus on FIG. 5 is a critical feature of the invention. Since it forms a single row of pins on the module 10, the pins can be easily connected directly to the expansion bus connectors without having to resort to multiple layer boards to route the PC board tracks from the module 10 to the expansion bus connectors A, B, C, D. Furthermore, as mentioned above, the present invention includes both microprocessor modules as illustrated in FIG. 3, as well as peripheral controller modules such as display controller modules, Ethernet control modules, and PCMCIA compatible modules for extended memory (RAM, ROM, EEPROM, flash memory, etc.), as well as for modem, fax, and network interfaces, and also for wireless communication devices. By providing an identical pin configuration for the ISA buses, the various modules can easily be connected to one another.

A further feature of the invention is illustrated in FIG. 6. FIG. 6 illustrates a card 54 having a mounting site 56 for a module having a pin configuration as described above with reference to FIG. 4. The card 54 provides an integrated way for system development in standard ISA passive backplane systems. The card includes an AT-bus and a PC/104 bus, and occupies a single slot in an AT-class (16-bit) passive backplane. This allows development to be performed using a terminal on a serial port as a console. A standard VGA or SVGA display controller can be plugged into another slot on the backplane if desired. Instead, a PC/104 display controller can be installed directly on the PC/104 header 58 on the card 54. Since the module 10 is fully compatible with PC/AT ISA, a wide selection of hardware peripherals may be integrated. The ISA-compatible bus allows an OEM to easily interface his proprietary hardware design with the module 10. Furthermore, the standard BIOS and embedded DOS allows application software to be developed using standard desk top PCs and standard development tools for implementation on the system using one or more modules of the present invention. It will be appreciated that, depending on the nature of the module, the size of the module and the number of pins may vary, however it is an important feature of this invention that the pins for the ISA bus retain their configuration in each module to allow the modules to be readily connected to one another as illustrated in FIG. 7 in which different modules 60, 62, 64 of the invention are connected to each other by means of bus lines 66, 68 extending between the ISA compatible bus pins indicated by reference numerals 70, 72, 74, respectively. 

We claim:
 1. A multi-chip module comprisinga plurality of functional circuits provided on a substrate and defining a plurality of signal inputs and outputs, and a plurality of module pins secured in a single row along the periphery of the substrate and connected to the inputs and outputs, the module pins including a set of 91 signal pins, two ground pins and a power pin, defining an ISA bus, the signal pins having a configuration complying in number and signal type with the IEEE-P996 requirements, wherein the module is rectangular in shape and has a first side, a second side opposite the first side, a third side, and a fourth side, an upper surface, a lower surface, and a peripheral wall; and wherein the pins defining the ISA bus extend from the peripheral wall and along the first side and at least partially along the third and fourth sides of the module.
 2. The multi-chip module of claim 1, wherein the module pins comprise 240 gull wing pins.
 3. The multi-chip module of claim 1, wherein the functional circuits include a central processing unit.
 4. The multi-chip module of claim 3, further comprising a watchdog timer means for resetting the central processing unit.
 5. The multi-chip module of claim 3, wherein the functional circuits further include two serial ports, a parallel port, a hard disk controller, a floppy disk controller, a keyboard interface, a DRAM interface and flash memory.
 6. The multi-chip module of claim 1, wherein the functional circuits include a PCMCIA interface.
 7. The multi-chip module of claim 1, wherein the functional circuits include an Ethernet interface.
 8. The multi-chip module of claim 1, wherein the functional circuits include a display controller.
 9. The multi-chip module of claim 1, wherein the substrate comprises a printed circuit board and the functional circuits comprise semiconductor devices secured to the printed circuit board.
 10. A multi-chip module comprisinga plurality of functional circuits provided on a substrate and defining a plurality of signal inputs and outputs, and a plurality of module pins secured in a single row along the periphery of the substrate and connected to the inputs and outputs, the module pins including a set of 91 signal pins, two ground pins and a power pin, defining an ISA bus, the signal pins having a configuration complying in number and signal type with the IEEE-P996 requirements, wherein the module is rectangular in shape, having a first side, a second side opposite the first side, a third side, and a fourth side, and is defined by an upper surface, a lower surface, and a peripheral wall, and wherein the plurality of pins extend from the peripheral wall, and wherein the pins of the ISA bus comprisepin 38 corresponding to signal IOCHCK; pin 39 corresponding to signal SD07; pin 40 corresponding to signal RESETDRV; pin 41 corresponding to signal SD06; pin 42 corresponding to signal SD05; pin 43 corresponding to signal IRQ9; pin 44 corresponding to signal SD04; pin 45 corresponding to signal SD03; pin 46 corresponding to signal DRQ2; pin 47 corresponding to signal DRQOUT-; pin 48 corresponding to signal SD02; pin 49 corresponding to signal SD01-; pin 50 corresponding to signal 0WS-; pin 51 corresponding to signal SD00; pin 52 corresponding to signal IOCHRDY; pin 53 corresponding to signal SBHE-; pin 54 corresponding to signal MEMSC16-; pin 55 corresponding to signal AEN; pin 56 corresponding to signal SMEMW-; pin 57 corresponding to signal LA23; pin 58 corresponding to signal IOCS16-; pin 59 corresponding to signal SA19; pin 60 corresponding to signal SMEMR-; pin 61 corresponding to signal LA22; pin 62 corresponding to signal IRQ10; pin 63 corresponding to signal SA18; pin 64 corresponding to signal IOW-; pin 65 corresponding to signal LA21; pin 66 corresponding to signal IRQ11; pin 67 corresponding to signal GND; pin 68 corresponding to signal SA17; pin 69 corresponding to signal IOR-; pin 70 corresponding to signal LA20; pin 71 corresponding to signal IRQ12; pin 72 corresponding to signal SA16; pin 73 corresponding to signal DACK3-; pin 74 corresponding to signal LA19; pin 75 corresponding to signal IRQ15; pin 76 corresponding to signal SA15; pin 77 corresponding to signal DRQ3; pin 78 corresponding to signal LA18; pin 79 corresponding to signal IRQ14; pin 80 corresponding to signal SA14; pin 81 corresponding to signal DACK1-; pin 82 corresponding to signal LA17; pin 83 corresponding to signal DACK0-; pin 84 corresponding to signal SA13; pin 85 corresponding to signal VCC; pin 86 corresponding to signal DRQ1-; pin 87 corresponding to signal MEMR-; pin 88 corresponding to signal DRQ0; pin 89 corresponding to signal SA12; pin 90 corresponding to signal REFRESH-; pin 91 corresponding to signal MEMW-; pin 92 corresponding to signal DACK5-; pin 93 corresponding to signal SA11; pin 94 corresponding to signal SYSCLK; pin 95 corresponding to signal SD08; pin 96 corresponding to signal DRQ5; pin 97 corresponding to signal SA10; pin 98 corresponding to signal IRQ7; pin 99 corresponding to signal IRQ7OUT; pin 100 corresponding to signal SD09; pin 101 corresponding to signal DACK6-; pin 102 corresponding to signal GND; pin 103 corresponding to signal SA09; pin 104 corresponding to signal IRQ6; pin 105 corresponding to signal IRQ6OUT; pin 106 corresponding to signal SD10; pin 107 corresponding to signal DRQ6; pin 108 corresponding to signal SA08; pin 109 corresponding to signal IRQ5; pin 110 corresponding to signal SD11; pin 111 corresponding to signal DACK7-; pin 112 corresponding to signal SA07; pin 113 corresponding to signal IRQ4; pin 114 corresponding to signal SD12; pin 115 corresponding to signal DRQ7; pin 116 corresponding to signal SA06; pin 117 corresponding to signal IRQ3; pin 118 corresponding to signal SD13; pin 119 corresponding to signal SA05; pin 120 corresponding to signal DACK2-; pin 121 corresponding to signal SD14; pin 122 corresponding to signal MASTER-; pin 123 corresponding to signal SA04; pin 124 corresponding to signal TC; pin 125 corresponding to signal SD15; pin 126 corresponding to signal SA03; pin 127 corresponding to signal BALE; pin 128 corresponding to signal SA02; pin 129 corresponding to signal SA01; pin 130 corresponding to signal OSC; and pin 131 corresponding to signal SA00.
 11. The multi-chip module of claim 10, wherein the pins of the ISA bus extend along the first side and at least partially along the third and fourth sides.
 12. A multi-chip module comprisinga plurality of functional circuits encapsulated in a rectangular housing, the housing having an upper surface and a lower surface, and a peripheral wall extending along a first side, a second side opposite the first side, a third side and a fourth side; and a plurality of module pins extending laterally from the peripheral wall and including a set of 91 signal pins, two ground pins and a power pin, defining an ISA bus, the signal pins complying in number and signal type with the IEEE-P996 requirements, and the bus pins extending along the first side and at least partially along the third and fourth sides of the housing.
 13. The multi-chip module of claim 12, wherein the module pins comprise 240 gull wing pins.
 14. The multi-chip module of claim 12, wherein the functional circuits include a central processing unit.
 15. The multi-chip module of claim 14, further comprising a watchdog timer means for resetting the central processing unit.
 16. The multi-chip module of claim 14, wherein the functional circuits further include two serial ports, a parallel port, a hard disk controller, a floppy disk controller, a keyboard interface, a DRAM interface and flash memory.
 17. The multi-chip module of claim 12, wherein the functional circuits include a PCMCIA interface.
 18. The multi-chip module of claim 12, wherein the functional circuits include an Ethernet interface.
 19. The multi-chip module of claim 12, wherein the functional circuits include a display controller.
 20. The multi-chip module of claim 12, wherein the functional circuits comprise semiconductor devices that are mounted on a printed circuit board.
 21. A module family comprisinga plurality of functionally different modules, wherein each module has a plurality of pins and the pins of each module include a set of 91 signal pins, two ground pins, and a power pin, defining an ISA bus complying in number and signal type with the IEEE-P996 requirements, wherein each module comprises at least one functional circuit encapsulated in a rectangular housing, the housing having an upper surface and a lower surface, and a peripheral wall extending along a first side, a second side opposite the first side, a third side, and a fourth side, and wherein the pins of the module extend laterally from the peripheral wall, and the pins which define the ISA bus extend along the first side and at least partially along the third and fourth sides of the housing.
 22. The module family of claim 21, wherein the pins of the modules comprise gull wing pins.
 23. The module family of claim 21, wherein the at least one functional circuit of at least one of the modules includes a central processing unit.
 24. The module family of claim 23, further comprising a watchdog timer means for resetting the central processing unit.
 25. The module family of claim 23, wherein said at least one module that includes a central processing unit, further includes two serial ports, a parallel port, a hard disk controller, a floppy disk controller, a keyboard interface, a DRAM interface and flash memory.
 26. The module family of claim 21, wherein the at least one functional circuit of at least one of the modules includes a PCMCIA interface.
 27. The module family of claim 21, wherein the at least one functional circuit of at least one of the modules includes an Ethernet interface.
 28. The module family of claim 21, wherein the at least one functional circuit of at least one of the modules includes a display controller.
 29. The module family of claim 21, wherein, in each module, the functional circuits include semiconductor devices that are mounted on a printed circuit board.
 30. A multi-chip module comprising:a plurality of functional circuits provided on a substrate and defining a plurality of signal inputs and outputs; and a plurality of module pins secured in a single row along the periphery of the substrate and coupled to the inputs and outputs, the module pins including a set of 94 contiguous pins which define an ISA bus comprising:1. IOCHCK;
 2. SD07;
 3. RESETDRV;
 4. SD06;
 5. SD05;
 6. IRQ9;
 7. SD04;
 8. SD03;
 8. DRQ2;
 10. DRQOUT-;
 11. SD02;
 12. SD01-;
 13. 0WS-;
 14. SD00;
 15. IOCHRDY;
 16. SBHE-;
 17. MEMSC16-;
 18. AEN;
 19. SMEMW-;
 20. LA23;
 21. IOCS16-;
 22. SA19;
 23. SMEMR-;
 24. LA22;
 25. IRQ10;
 26. SA18;
 27. IOW-;
 28. LA21;
 29. IRQ11;
 30. GND;
 31. SA17;
 32. IOR-;
 33. LA20;
 34. IRQ12;
 35. SA16;
 36. DACK3-;
 37. LA19;
 38. IRQ15;
 39. SA15;
 40. DRQ3;
 41. LA18;
 42. IRQ14;
 43. SA14;
 44. DACK1-;
 45. LA17;
 46. DACK0-;
 47. SA13;
 48. VCC;
 49. DRQ1-;
 50. MEMR-;
 51. DRQ0;
 52. SA12;
 53. REFRESH-;
 54. MEMW-;
 55. DACK5-;
 56. SA11;
 57. SYSCLK;
 58. SD08;
 59. DRQ5;
 60. SA10;
 61. IRQ7;
 62. IRQ7OUT;
 63. SD09;
 64. DACK6-;
 65. GND;
 66. SA09;
 67. IRQ6;
 68. IRQ6OUT;
 69. SD10;
 70. DRQ6;
 71. SA08;
 72. IRQ5;
 73. SD11;
 74. DACK7-;
 75. SA07;
 76. IRQ4;
 77. SD12;
 78. DRQ7;
 79. SA06;
 80. IRQ3;
 81. SD13;
 82. SA05;
 83. DACK2-;
 84. SD14;
 85. MASTER-;
 86. SA04;
 87. TC;
 88. SD15;
 89. SA03;
 90. BALE;
 91. SA02;
 92. SA01;
 93. OSC; and
 94. SA00.
 31. The multi-chip module of claim 30 wherein the module comprises 240 pins, and the 94 pins of the ISA bus comprise pins 38 to
 131. 32. The multi-chip module of claim 31 wherein the 94 pins of the ISA bus are numbered in ascending order.
 33. The multi-chip module of claim 30 wherein the module comprises 240 pins, and the 94 pins of the ISA bus comprise pins 110 to
 203. 34. The multi-chip module of claim 33 wherein the 94 pins of the ISA bus are numbered in descending order.
 35. The multi-chip module of claim 30 wherein the module is rectangular in shape, having a first side, a second side opposite the first side, a third side, and a fourth side, and is defined by an upper surface, a lower surface, and a peripheral wall, and wherein the plurality of pins extend from the peripheral wall.
 36. The multi-chip module of claim 35 wherein the pins of the ISA bus extend along the first side and at least partially along the third and fourth sides.
 37. The multi-chip module of claim 30 wherein the functional circuits include a central processing unit.
 38. The multi-chip module of claim 37 further including a watchdog timer for resetting the central processing unit.
 39. The multi-chip module of claim 37 wherein the functional circuits include two serial ports, a parallel port, a hard disk controller, a floppy disk controller, a keyboard interface, a DRAM interface and flash memory.
 40. The multi-chip module of claim 30 wherein the functional circuits include a PCMCIA interface.
 41. The multi-chip module of claim 30 wherein the functional circuits include an Ethernet interface.
 42. The multi-chip module of claim 30 wherein the functional circuits include a display controller.
 43. The multi-chip module of claim 30 wherein the substrate comprises a printed circuit board, and the functional circuits comprise semiconductor devices mounted on the printed circuit board. 